Expression of miR-126 and its potential function in coronary artery disease

Clinical Significance of MicroRNAs, Long Non-Coding RNAs, and CircRNAs in Cardiovascular Diseases

Based on recent research, the non-coding genome is essential for controlling genes and genetic programming during development, as well as for health and cardiovascular diseases (CVDs). The microRNAs (miRNAs), lncRNAs (long ncRNAs), and circRNAs (circular RNAs) with significant regulatory and structural roles make up approximately 99% of the human genome, which does not contain proteins. Non-coding RNAs (ncRNA) have been discovered to be essential novel regulators of cardiovascular risk factors and cellular processes, making them significant prospects for advanced diagnostics and prognosis evaluation. Cases of CVDs are rising due to limitations in the current therapeutic approach; most of the treatment options are based on the coding transcripts that encode proteins. Recently, various investigations have shown the role of nc-RNA in the early diagnosis and treatment of CVDs. Furthermore, the development of novel diagnoses and treatments based on miRNAs, lncRNAs, and circRNAs could be more helpful in the clinical management of patients with CVDs. CVDs are classified into various types of heart diseases, including cardiac hypertrophy (CH), heart failure (HF), rheumatic heart disease (RHD), acute coronary syndrome (ACS), myocardial infarction (MI), atherosclerosis (AS), myocardial fibrosis (MF), arrhythmia (ARR), and pulmonary arterial hypertension (PAH). Here, we discuss the biological and clinical importance of miRNAs, lncRNAs, and circRNAs and their expression profiles and manipulation of non-coding transcripts in CVDs, which will deliver an in-depth knowledge of the role of ncRNAs in CVDs for progressing new clinical diagnosis and treatment.

Role of the renin-angiotensin system in the pathophysiology of coronary heart disease and heart failure: Diagnostic biomarkers and therapy with drugs and natural products

The renin-angiotensin system (RAS) plays a pivotal role in blood pressure regulation. In some cases, this steering mechanism is affected by various deleterious factors (mainly via the overactivation of the RAS) causing cardiovascular damage, including coronary heart disease (CHD) that can ultimately lead to chronic heart failure (CHF). This not only causes cardiovascular disability and absenteeism from work but also imposes significant healthcare costs globally. The incidence of cardiovascular diseases has escalated exponentially over the years with the major outcome in the form of CHD, stroke, and CHF. The involvement of the RAS in various diseases has been extensively researched with significant limelight on CHD. The RAS may trigger a cascade of events that lead to atherosclerotic mayhem, which causes CHD and related aggravation by damaging the endothelial lining of blood vessels via various inflammatory and oxidative stress pathways. Although there are various diagnostic tests and treatments available in the market, there is a constant need for the development of procedures and therapeutic strategies that increase patient compliance and reduce the associated side effects. This review highlights the advances in the diagnostic and treatment domains for CHD, which would help in subjugating the side effects caused by conventional therapy.

Extracellular Vesicles in Coronary Artery Disease

Coronary artery disease (CAD) is the leading cause of death and disability worldwide. Despite recent progress in the diagnosis and treatment of CAD, evidence gaps remain, including pathogenesis, the most efficient diagnostic strategy, prognosis of individual patients, monitoring of therapy, and novel therapeutic strategies. These gaps could all be filled by developing novel, minimally invasive, blood-based biomarkers. Potentially, extracellular vesicles (EVs) could fill such gaps. EVs are lipid membrane particles released from cells into blood and other body fluids. Because the concentration, composition, and functions of EVs change during disease, and because all cell types involved in the development and progression of CAD release EVs, currently available guidelines potentially enable reliable and reproducible measurements of EVs in clinical trials, offering a wide range of opportunities. In this chapter, we provide an overview of the associations reported between EVs and CAD, including (1) the role of EVs in CAD pathogenesis, (2) EVs as biomarkers to diagnose CAD, predict prognosis, and monitor therapy in individual patients, and (3) EVs as new therapeutic targets and/or drug delivery vehicles. In addition, we summarize the challenges encountered in EV isolation and detection, and the lack of standardization, which has hampered real clinical applications of EVs. Since most conclusions are based on animal models and single-center studies, the knowledge and insights into the roles and opportunities of EVs as biomarkers in CAD are still changing, and therefore, the content of this chapter should be seen as a snapshot in time rather than a final and complete compendium of knowledge on EVs in CAD.

microRNAs Associated with Carotid Plaque Development and Vulnerability: The Clinician's Perspective

Ischemic stroke (IS) related to atherosclerosis of large arteries is one of the leading causes of mortality and disability in developed countries. Atherosclerotic internal carotid artery stenosis (ICAS) contributes to 20% of all cerebral ischemia cases. Nowadays, atherosclerosis prevention and treatment measures aim at controlling the atherosclerosis risk factors, or at the interventional (surgical or endovascular) management of mature occlusive lesions. There is a definite lack of the established circulating biomarkers which, once modulated, could prevent development of atherosclerosis, and consequently prevent the carotid-artery-related IS. Recent studies emphasize that microRNA (miRNA) are the emerging particles that could potentially play a pivotal role in this approach. There are some research studies on the association between the expression of small non-coding microRNAs with a carotid plaque development and vulnerability. However, the data remain inconsistent. In addition, all major studies on carotid atherosclerotic plaque were conducted on cell culture or animal models; very few were conducted on humans, whereas the accumulating evidence demonstrates that it cannot be automatically extrapolated to processes in humans. Therefore, this paper aims to review the current knowledge on how miRNA participate in the process of carotid plaque formation and rupture, as well as stroke occurrence. We discuss potential target miRNA that could be used as a prognostic or therapeutic tool.

Reductions in extracellular vesicle-associated microRNA-126 levels in coronary blood after acute myocardial infarction: A retrospective study

Background

Acute Myocardial Infarction (AMI) is a kind of cardiovascular disease with high mortality and incidence. Extracellular vesicles (EVs) and microRNA-126 (miR-126) are known to play important role in the development and prognosis of several cardiovascular diseases. Therefore, this study aimed to investigate the changes in Extracellular vesicle (EV)-associated miR-126 levels in the coronary blood of patients with AMI to explore the relationship between miR-126 levels and AMI.

Materials and methods

We analyzed EV-associated miR-126 in the coronary blood of patients with AMI and stable coronary artery disease (SCAD) using quantitative reverse transcription polymerase chain reaction (qRT-PCR).

Results

We tested the coronary blood of 20 patients with AMI and 20 with SCAD. The mean age of the patients was 58.8 ± 10.3 years and 32 (80%) were men. We observed that the EV-associated miR-126 levels were lower in patients with AMI [median = 0.13; interquartile range (IQR): 0.08–0.22] than in patients with SCAD (median = 0.37; IQR: 0.26–0.48) (P < 0.001). In addition, the levels of miR-126 were negatively associated with the Thrombolysis in Myocardial Infarction (TIMI) score (r = −0.66, P = 0.001).

Conclusion

Reduction of EV-associated miR-126 levels in the coronary blood of patients with AMI may be involved in acute coronary thrombosis events.

Clinical Application of Serum microRNAs in Atherosclerotic Coronary Artery Disease

MicroRNAs (miRs) are promising diagnostic, prognostic and therapeutic biomolecules for atherosclerotic cardiovascular disease. Atherosclerotic occlusive disease concerns a large population of patients, carrying the highest incidence of fatal and non-fatal adverse events, such as myocardial infarction, ischemic stroke, and limb ischemia, worldwide. Consistently, miRs are involved in regulation and pathogenesis of atherosclerotic coronary artery disease (CAD), acute coronary syndromes (ACS), both with ST-segment (STEMI) and non-ST segment elevation myocardial infarctions (NSTEMI), as well as cardiac remodeling and fibrosis following ACS. However, the genetic and molecular mechanisms underlying adverse outcomes in CAD are multifactorial, and sometimes difficult to interpret for clinicians. Therefore, in the present review paper we have focused on the clinical meaning and the interpretation of various miRs findings, and their potential application in routine clinical practice.

PCSK9 and LRP6: potential combination targets to prevent and reduce atherosclerosis

Coronary artery disease (CAD) is a disease characterized by atherosclerosis formation which causes sudden cardiac death. The prevalence of CAD is expected to increase by 2030. Atherosclerosis started from accumulation of LDL in the blood vessels, followed by endothelial cell activation and dysfunction. PCSK9 is a gene that plays an important role in the creation of atherosclerotic plaque through induced degradation of LDLRs. Inhibition of PCSK9 gene resulted in a decrease of LDLRs degradation and reduction in LDL-C levels. LRP6, as well as its mutation, is a coreceptor that contributes to atherosclerosis through the canonical Wnt/β-catenin pathway. By employing EMPs mediated miRNA-126, third-generation antisense against miR-494-3p (3 GA-494), and recombinant Wnt mouse Wnt3a (rmWnt3a), the inhibition of LRP6 could reduce VSMCs proliferation, enhancing anti-inflammatory macrophages, and diminished bioactive lipids component, respectively. Those mechanisms lead to the stabilization and reduction of atherosclerosis plaques.

Diagnostic value of cardiac miR-126-5p, miR-134-5p, and miR-499a-5p in coronary artery disease-induced sudden cardiac death

Background

The identification of coronary artery disease-induced sudden cardiac death (CAD-SCD) has always been a medical challenge. MicroRNAs (miRNAs) played vital roles in pathogenesis processes and served as potential biomarkers for cardiovascular and many other diseases. The aim of this study was to investigate the diagnostic value of the specific miRNAs for CAD-SCD.

Methods

A total of 30 autopsy-verified CAD-SCD victims were selected, including 18 individuals who experienced more than once asymptomatic myocardial ischemia (CAD-activated SCD) and 12 victims without prominent pathological features of insufficient blood supply (CAD-silent SCD). Meanwhile, 30 traumatic victims were enrolled as controls. Systematic postmortem examinations were performed in all study population. The expressions of cardiac miR-126-5p, miR-134-5p, and miR-499a-5p were analyzed by real-time quantitative polymerase chain reaction (RT-qPCR).

Results

RT-qPCR showed significant downregulations of miR-126-5p and miR-499a-5p in CAD-SCD victims, with no obvious difference in miR-134-5p. Receiver-operating characteristic analysis revealed the diagnostic performance of miR-126-5p (areas under the curve [AUC] = 0.76) and validated miR-499a-5p (AUC = 0.82) as a sensitive marker. Additionally, the decreased expression of the two specific cardio-miRNAs was detected for discriminating CAD-silent SCD and CAD-activated SCD. Compared with the limited diagnostic value of single miR-126-5p and miR-499a-5p, their combination could achieve better discriminative capacity (AUC = 0.82, sensitivity = 91.7%, specificity = 77.8%).

Conclusion

Cardiac miR-126-5p and miR-499a-5p presented good diagnostic abilities for CAD-SCD, and their combination could help evaluate CAD condition. These targeted miRNAs as novel biomarkers are expected to be useful to discriminate the detailed causes in real SCD cases.

Novel Biomarkers of Atherosclerotic Vascular Disease-Latest Insights in the Research Field

The atherosclerotic vascular disease is a cardiovascular continuum in which the main role is attributed to atherosclerosis, from its appearance to its associated complications. The increasing prevalence of cardiovascular risk factors, population ageing, and burden on both the economy and the healthcare system have led to the development of new diagnostic and therapeutic strategies in the field. The better understanding or discovery of new pathophysiological mechanisms and molecules modulating various signaling pathways involved in atherosclerosis have led to the development of potential new biomarkers, with key role in early, subclinical diagnosis. The evolution of technological processes in medicine has shifted the attention of researchers from the profiling of classical risk factors to the identification of new biomarkers such as midregional pro-adrenomedullin, midkine, stromelysin-2, pentraxin 3, inflammasomes, or endothelial cell-derived extracellular vesicles. These molecules are seen as future therapeutic targets associated with decreased morbidity and mortality through early diagnosis of atherosclerotic lesions and future research directions.

Dysregulation in the Expression of Platelet Surface Receptors in Acute Coronary Syndrome Patients-Emphasis on P2Y12

The pathological conditions caused by blood platelet activation constitute a fundamental core in the pathogenesis of Acute Coronary Syndrome (ACS). The hyperactivity of platelets in ACS is well-documented, but there is still little research into the molecular basis of phenotypic changes in platelet functionality. To expand the knowledge of this phenomenon, we analyzed the disturbances in the expression of several key platelet receptors and the aspect of regulating potential abnormalities. Platelet surface receptors are responsible for maintaining the hemostatic balance, platelet interaction with immune cells, and support of the coagulation cascade leading to occlusion of the vessel lumen. Due to their prominent role, platelet receptors constitute a major target in pharmacological treatment. Our work aimed to identify the molecular alteration of platelet surface receptors, which showed augmented mRNA expression of P2Y12, GP1BB, ITGA2B, and ITGB3 and increased protein concentrations of P2Y12 and GP IIb/IIIa in ACS. The upregulation of the P2Y12 level was also confirmed by confocal and cytometric visualization. Furthermore, we evaluated the expression of two microRNAs: miR-223-3p and miR-126-3p, which were suggested to regulate platelet P2Y12 expression. Results of our study present new insight into the molecular background of ACS.

Overexpression of miR-126 Protects Hypoxic-Reoxygenation-Exposed HUVEC Cellular Injury through Regulating LRP6 Expression

The aim of the study was to explore the clinical impact of circulatory miR-126 as a candidate for novel biomarker in patients with coronary artery disease (CAD) and its protective role against hypoxia/reoxygenation- (H/R-) exposed HUVEC cellular injury. A total of 278 subjects, which included 153 subjects with angiographically confirmed CAD, 70 unstable angina subjects, and 55 healthy individuals, along with 18-hour HR-induced HUVECs were recruited in this study. Plasma miR-126 levels were significantly downregulated in stable and unstable CAD patients as well as 18-hour HR-exposed HUVECs as compared with controls. Stable and unstable CAD subjects were significantly differentiated from healthy individuals with a predictive value of AUC 0.903 and 0.923, respectively. Moreover, peripheral circulatory miR-126 expressions in elderly (71-90 years) stable and unstable CAD patients were comparatively lower than younger (30-50 years) subjects. The caspase-3 activity, intracellular ROS concentrations, and cellular viabilities were evidently increased in 18-hour HR-exposed HUVECs than in normal cells ( $P<0.001$ ). On the contrary, mimic expressions of miR-126 prominently reduced caspase-3 activity and intracellular ROS levels and markedly enhanced HUVEC cellular viabilities ( $P<0.001$ ). LRP6 expressions were significantly elevated in HR-induced HUVECs, whereas overexpression of miR-126 remarkably decreased LRP6 expressions ( $P<0.001$ ). Plasma miR-126 could be used as a novel biomarker for early prediction of CAD subjects. Overexpression of miR-126 significantly improved HUVEC cellular viabilities by downregulation of LRP6 protein expression, suggesting a potential therapeutic target for CAD patients.

Plasma-derived exosomes implement miR-126-associated regulation of cytokines secretion in PBMCs of CHF patients in vitro

Background The investigation of regulatory effects of intra-exosomal compounds, especially microRNAs, has promising therapeutic prospects in the treatment of numerous diseases, including cardiovascular disorders. In this study, we investigated the effect of healthy donors` plasma exosomes (HDPE) on the production of cytokines by PBMC cells of patients with congestive heart failure (CHF) and showed the integral role of miRNA-126 in CHF-mediated changes of mononuclear paracrine secretion. Methods Peripheral blood mononuclear cells (PBMСs) were isolated from a peripheral blood of fifteen patients with CHF (age, 66,8±9,8 years; left ventricular ejection fraction, 44±19%). The concentration of cytokines (IL-10, ICAM-1, VEGF-A, TNF-α and MCP-1) in culture medium and PBMCs was measured by ELISA. The level of miRNA-126 expression in PBMCs was performed by real-time PCR. Results Dramatic increase of ICAM-1 level in activated PBMCs of CHF patients, as well as an increase of the IL-10, ICAM-1 and TNF-α levels in the culture medium was observed. It was accompanied by CHF-related miRNA-126 overexpression in PBMCs. HDPE treatment distinguished by a tendency to reduction in miRNA-126 expression by CHF PBMCs and correlated with upregulation of IL-10, ICAM-1, TNF-α and MCP-1 with normalization of cytokines secretion. Conclusions The altered paracrine secretion of cytokines by CHF PBMCs and miRNA-126 overexpression in vitro was found. HDPE treatment modulated production and secretion of most of studied cytokines by CHF PBMCs in vitro. The experimental application of exosomes for the modulation of paracrine secretion and PBMCs cellular functions may be promising for CVD therapy, including endothelial dysfunction and CHF.

Plasma Exosomes at the Late Phase of Remote Ischemic Pre-conditioning Attenuate Myocardial Ischemia-Reperfusion Injury Through Transferring miR-126a-3p

Background: Remote ischemic pre-conditioning (RIPC) alleviated the myocardial ischemia-reperfusion injury, yet the underlying mechanisms remain to be fully elucidated, especially at the late phase. Searching a key component as a transfer carrier may provide a novel insight into RIPC-mediated cardioprotection in the condition of myocardial ischemia-reperfusion.

Objective: To investigate the cardioprotective effect of plasma exosomes at the late phase of RIPC and its potential signaling pathways involved.

Methods and Results: Exosomes were isolated from the plasma of rats 48 h after the RIPC or control protocol. Although the total plasma exosomes level had no significant change at the late phase of RIPC (RIPC-exosome) compared with the control exosomes (Control-exosome), the RIPC-exosome afforded remarkable protection against myocardial ischemia-reperfusion (MI/R) injury in rats and hypoxia-reoxygenation (H/R) injury in cells. The miRNA array revealed significant enrichment of miR-126a-3p in RIPC-exosome. Importantly, both miR-126a-3p inhibitor and antagonist significantly blunted the cardioprotection of RIPC-exosome in H/R cells and MI/R rats, respectively, while miR-126a-3p mimic and agomir showed significant cardioprotection against H/R injury in cells and MI/R injury in rats. Mechanistically, RIPC-exosome, especially exosomal miR-126a-3p, activated the reperfusion injury salvage kinase (RISK) pathway by enhancing the phosphorylation of Akt and Erk1/2, and simultaneously inhibited Caspase-3 mediated apoptotic signaling.

Conclusions: Our findings reveal a novel myocardial protective mechanism that plasma exosomes at the late phase of RIPC attenuate myocardial ischemia-reperfusion injury via exosomal miR-126a-3p.

Circulating microRNA-126 as an Independent Risk Predictor of Coronary Artery Disease: A Case-Control Study

CONTEXT

Circulating microRNAs (miR) have revolutionized the field of molecular biology owing to their potential as a diagnostic as well as a prognostic biomarker of cardiovascular disease and dysfunctions. The present study aims to identify the circulating miR-126 and -122 as an independent risk predictors of coronary artery disease cases.

METHODS AND MATERIAL

Blood samples were collected from coronary artery disease cases (n=100) and non-CAD cases (n=100). Serum RNA was isolated by Trizol method. MiR levels were measured by quantitative real-time polymerase chain reaction with the specific primer probe set.

RESULTS

MiR-126 levels were significantly down-regulated in CAD cases compared to non-CAD cases (controls) (80.0% vs. 39.0%, χ2=14.95, p<0.001). The level of miR-122 was significantly up-regulated in CAD cases in comparison to its non-CAD variant (14.0% vs. 63.0%, χ2=21.23, p<0.001). Multivariate analysis found chest pain (OR=37.07, 95% CI=3.21-169.04, p=0.017) and miR-126 (OR=0.01, 95% CI=0.00-0.63, p=0.030) as independent risk predictors of CAD.

CONCLUSION

The results of our study show the potential of circulating miR-126 as a novel non-invasive biomarker in the risk prediction of CAD. Further unraveling of the role of miR-122 and miR-126 in the pathogenesis and progression of CAD will add to our understanding of the disease process leading to a new diagnostic approach.

HIGHLIGHTS

Mir-122 and -126 significantly differentiate non CAD cases from angiographically proven CAD casesChest pain and miR-126 might work as an independent risk predictor of coronary artery disease.

How Are Epigenetic Modifications Related to Cardiovascular Disease in Older Adults?

The rate of aging has increased globally during recent decades and has led to a rising burden of age-related diseases such as cardiovascular disease (CVD). At the molecular level, epigenetic modifications have been shown recently to alter gene expression during the life course and impair cellular function. In this regard, several CVD risk factors, such as lifestyle and environmental factors, have emerged as key factors in epigenetic modifications within the cardiovascular system. In this study, we attempted to summarized recent evidence related to epigenetic modification, inflammation response, and CVD in older adults as well as the effect of lifestyle modification as a preventive strategy in this age group. Recent evidence showed that lifestyle and environmental factors may affect epigenetic mechanisms, such as DNA methylation, histone acetylation, and miRNA expression. Several substances or nutrients such as selenium, magnesium, curcumin, and caffeine (present in coffee and some teas) could regulate epigenetics. Similarly, physical inactivity, alcohol consumption, air pollutants, psychological stress, and shift working are well-known modifiers of epigenetic patterns. Understanding the exact ways that lifestyle and environmental factors could affect the expression of genes could help to influence the time of incidence and severity of aging-associated diseases. This review highlighted that a healthy lifestyle throughout the life course, such as a healthy diet rich in fibers, vitamins, and essential elements, and specific fatty acids, adequate physical activity and sleep, smoking cessation, and stress control, could be useful tools in preventing epigenetic changes that lead to impaired cardiovascular function.

Adding a "Notch" to Cardiovascular Disease Therapeutics: A MicroRNA-Based Approach

Dysregulation of the Notch pathway is implicated in the pathophysiology of cardiovascular diseases (CVDs), but, as of today, therapies based on the re-establishing the physiological levels of Notch in the heart and vessels are not available. A possible reason is the context-dependent role of Notch in the cardiovascular system, which would require a finely tuned, cell-specific approach. MicroRNAs (miRNAs) are short functional endogenous, non-coding RNA sequences able to regulate gene expression at post-transcriptional levels influencing most, if not all, biological processes. Dysregulation of miRNAs expression is implicated in the molecular mechanisms underlying many CVDs. Notch is regulated and regulates a large number of miRNAs expressed in the cardiovascular system and, thus, targeting these miRNAs could represent an avenue to be explored to target Notch for CVDs. In this Review, we provide an overview of both established and potential, based on evidence in other pathologies, crosstalks between miRNAs and Notch in cellular processes underlying atherosclerosis, myocardial ischemia, heart failure, calcification of aortic valve, and arrhythmias. We also discuss the potential advantages, as well as the challenges, of using miRNAs for a Notch-based approach for the diagnosis and treatment of the most common CVDs.

miRNA-146a and miRNA-126 as Potential Biomarkers in Patients with Coronary Artery Disease and Generalized Periodontitis

The present study aims to compare the levels of micro-RNA-146a and micro-RNA-126 in oral subgingival plaque and coronary plaque from artery walls in patients with coronary artery disease who suffer from generalized periodontitis. A total of 75 participants were selected and grouped into three categories of 25 patients each: GP+CAD, GP, and HP groups. GP+CAD consisted of patients diagnosed with generalized periodontitis (GP) and coronary artery disease (CAD). The GP+CAD group was further divided into two groups—GP+CADa: where subgingival plaque samples were collected; GP+CADb group: where coronary plaque samples were collected while the patient underwent a coronary artery bypass grafting surgery. The GP group consisted of 25 patients diagnosed with only generalized periodontitis. The HP group consisted of 25 systemically and periodontally healthy controls. miRNA-146a and miRNA126 levels were assessed in subgingival plaque (SP) samples from all groups. Results revealed that miRNA-146a was expressed at higher levels and miRNA-126 was downregulated in the GP+CAD group. microRNAs in subgingival plaque samples showed a significant correlation with the coronary plaque samples in the GP+CAD group. miRNA-146a and miRNA-126 were present in coronary artery disease patients with periodontitis. These micro-RNAs may serve as risk biomarkers for coronary artery disease and generalized periodontitis.

Genetics of macrovascular complications in type 2 diabetes

Type 2 diabetes mellitus (T2DM) is a metabolic disorder that currently affects more than 400 million worldwide and is projected to cause 552 million cases by the year 2030. Long-term vascular complications, such as coronary artery disease, myocardial infarction, stroke, are the leading causes of morbidity and mortality among diabetic patients. The recent advances in genome-wide technologies have given a powerful impetus to the study of risk markers for multifactorial diseases. To date, the role of genetic and epigenetic factors in modulating susceptibility to T2DM and its vascular complications is being successfully studied that provides the accumulation of genomic knowledge. In the future, this will provide an opportunity to reveal the pathogenetic pathways in the development of the disease and allow to predict the macrovascular complications in T2DM patients. This review is focused on the evidence of the role of genetic variants and epigenetic changes in the development of macrovascular pathology in diabetic patients.

MicroRNA-126 Level Increases During Exercise Rehabilitation of Heart Failure with a Preserved Ejection Fraction

Objective

To evaluate the changes of plasma levels of miR-126 in heart failure with a preserved ejection fraction (HFpEF) patients undergoing an exercise rehabilitation intervention.

Methods

miR-126 levels in plasma were compared between 60HFpEF patients and 30 healthy volunteers. HFpEF patients underwent exercise rehabilitation for 12 weeks. Before and after rehabilitation, indicators of cardiac function, exercise tolerance, quality of life scores and miR-126 levels were measured and compared. Correlations between plasma levels of miR-126 and HFpEF were evaluated.

Results

The plasma levels of miR-126 in HFpEF patients were lower than those in healthy volunteers and increased significantly after exercise rehabilitation. HFpEF patients also showed significantly better cardiac function, exercise tolerance, and quality of life after rehabilitation. The results of Pearson correlation analysis and multiple linear regression showed that miR-126 levels were positively correlated with peak oxygen consumption (peak VO₂) and metabolic equivalents (METs), and inversely associated with score on the Minnesota Living with Heart Failure Questionnaire (MLHF) as well as plasma N-terminal pro-B-type natriuretic peptide (NT-proBNP) levels.

Conclusion

miR-126 levels are low expressed in plasma among HFpEF patients. Effective exercise rehabilitation in HFpEF patients may positively impact the plasma level of miR-126, which is probably associated with the restoration of cardiac function, exercise tolerance and quality of life. miR-126 may be a potential biomarker for evaluating the efficacy of exercise rehabilitation for HFpEF patients.

miR-126-3p is essential for CXCL12-induced angiogenesis

Atherosclerosis, in the ultimate stage of cardiovascular diseases, causes an obstruction of vessels leading to ischemia and finally to necrosis. To restore vascularization and tissue regeneration, stimulation of angiogenesis is necessary. Chemokines and microRNAs (miR) were studied as pro-angiogenic agents. We analysed the miR-126/CXCL12 axis and compared impacts of both miR-126-3p and miR-126-5p strands effects in CXCL12-induced angiogenesis. Indeed, the two strands of miR-126 were previously shown to be active but were never compared together in the same experimental conditions regarding their differential functions in angiogenesis. In this study, we analysed the 2D-angiogenesis and the migration assays in HUVEC in vitro and in rat's aortic rings ex vivo, both transfected with premiR-126-3p/-5p or antimiR-126-3p/-5p strands and stimulated with CXCL12. First, we showed that CXCL12 had pro-angiogenic effects in vitro and ex vivo associated with overexpression of miR-126-3p in HUVEC and rat's aortas. Second, we showed that 2D-angiogenesis and migration induced by CXCL12 was abolished in vitro and ex vivo after miR-126-3p inhibition. Finally, we observed that SPRED-1 (one of miR-126-3p targets) was inhibited after CXCL12 treatment in HUVEC leading to improvement of CXCL12 pro-angiogenic potential in vitro. Our results proved for the first time: 1-the role of CXCL12 in modulation of miR-126 expression; 2-the involvement of miR-126 in CXCL12 pro-angiogenic effects; 3-the involvement of SPRED-1 in angiogenesis induced by miR-126/CXCL12 axis.

Circulating microRNA-126 &122 in patients with coronary artery disease: Correlation with small dense LDL

BACKGROUND

Coronary artery disease (CAD) and stroke are major causes of cardiovascular diseases related deaths. Conventional risk factors cannot explain the changes in atherosclerosis. New and useful diagnostic markers are required. MicroRNAs are small, noncoding RNA that regulate the gene expression implicated in the pathogenesis of various cardiovascular diseases. Endothelial dysfunction is involved in the early event of the atherosclerosis process.

AIMS

The current study was designed to evaluate the vascular endothelium-enriched miRNAs would be altered in CAD patients.

METHODS

Circulating miR-126 & 122 levels were measured in serum from 78 CAD patients and 60 non CDA patients by qRT-PCR analysis.

RESULTS

MiR-122 was significantly down regulated in CAD patients (p = 0.001), however the level of miR-126 did not show any change (p = 0.507). Remarkably, the level of miR-126 was significantly decreased in patients with CAD and high small dense low density lipoprotein (sdLDL) level. The level of miR-126 was significantly increased when sdLDL was higher in patients with risk factors for CAD but did not have angiographically significant CAD.

CONCLUSION

. In CAD patient's, miR-126 level was lowered compared to non CAD patients, however the difference was not significant (0.507). However we found a direct relationship between endothelium-enriched miR-126 and sdLDL in patients with or without CAD. Our finding suggests that miR-126 may have a potential role in sdLDL cholesterol metabolism. Mir-122 plays a role in cholesterol biosynthesis and deteriorates the cardiovascular system through the process of inflammation, apoptosis, oxidative stress and ECM deposition in a number of cardiovascular diseases.

Regulation of miRNAs by Natural Antioxidants in Cardiovascular Diseases: Focus on SIRT1 and eNOS

Cardiovascular diseases (CVDs) are the most common cause of morbidity and mortality worldwide. The potential benefits of natural antioxidants derived from supplemental nutrients against CVDs are well known. Remarkably, natural antioxidants exert cardioprotective effects by reducing oxidative stress, increasing vasodilation, and normalizing endothelial dysfunction. Recently, considerable evidence has highlighted an important role played by the synergistic interaction between endothelial nitric oxide synthase (eNOS) and sirtuin 1 (SIRT1) in the maintenance of endothelial function. To provide a new perspective on the role of natural antioxidants against CVDs, we focused on microRNAs (miRNAs), which are important posttranscriptional modulators in human diseases. Several miRNAs are regulated via the consumption of natural antioxidants and are related to the regulation of oxidative stress by targeting eNOS and/or SIRT1. In this review, we have discussed the specific molecular regulation of eNOS/SIRT1-related endothelial dysfunction and its contribution to CVD pathologies; furthermore, we selected nine different miRNAs that target the expression of eNOS and SIRT1 in CVDs. Additionally, we have summarized the alteration of miRNA expression and regulation of activities of miRNA through natural antioxidant consumption.

Circulating microRNA as a Biomarker for Coronary Artery Disease

Coronary artery disease (CAD) is the leading cause of sudden cardiac death in adults, and new methods of predicting disease and risk-stratifying patients will help guide intervention in order to reduce this burden. Current CAD detection involves multiple modalities, but the consideration of other biomarkers will help improve reliability. The aim of this narrative review is to help researchers and clinicians appreciate the growing relevance of miRNA in CAD and its potential as a biomarker, and also to suggest useful miRNA that may be targets for future study. We sourced information from several databases, namely PubMed, Scopus, and Google Scholar, when collating evidentiary information. MicroRNAs (miRNA) are short, noncoding RNAs that are relevant in cardiovascular physiology and pathophysiology, playing roles in cardiac hypertrophy, maintenance of vascular tone, and responses to vascular injury. CAD is associated with changes in miRNA expression profiles, and so are its risk factors, such as abnormal lipid metabolism and inflammation. Thus, they may potentially be biomarkers of CAD. Nevertheless, there are limitations in using miRNA. These include cost and the presence of several confounding factors that may affect miRNA profiles. Furthermore, there is difficulty in the normalisation of miRNA values between published studies, due to pre-analytical variations in samples.

Expression of inflammatory factors and oxidative stress markers in serum of patients with coronary heart disease and correlation with coronary artery calcium score

Expression characteristics of inflammatory factors interleukin-23 and interleukin-35; oxidative stress markers of malondialdehyde, which is a final product of lipid peroxidation; superoxide dismutase; microRNA-126 and microRNA-146a in serum of patients with coronary heart disease were investigated. Correlation between these biomarkers and CACS (calcification score), as well as the underlying clinical significance were evaluated. A total of 192 patients diagnosed with coronary heart disease were recruited as the observation group, and 69 healthy adults who provided their blood samples were selected as the control group. Enzyme linked immunosorbent assay was carried out to measure the levels of inflammatory factors interleukin-23 and interleukin-35, and the levels of oxidative stress markers of malondialdehyde and superoxide dismutase in serum of the patients and healthy subjects. Real-time fluorescence-based quantitative PCR was performed to measure the expression levels of microRNA-126 and microRNA-146a in serum. The differences in expression of these biomarkers were analyzed, and correlation between these biomarkers and coronary artery calcium score were assessed. The differences in expression levels of interleukin-23, interleukin-35, malondialdehyde, superoxide dismutase, microRNA-126 and microRNA-146a were statistically significant in both groups. The expression levels of interleukin-23, interleukin-35, malondialdehyde, superoxide dismutase, microRNA-126 and microRNA-146a in the observation group were closely associated with severity of the disease. There were positive correlations between coronary artery calcium score and interleukin-23, interleukin-35, malondialdehyde, microRNA-126 and microRNA-146a, respectively; while a negative correlation existed between coronary artery calcium score and superoxide dismutase in the observation group. In conclusion, biomarkers interleukin-23, interleukin-35, malondialdehyde, superoxide dismutase, microRNA-126 and microRNA-146a were abnormally expressed in serum of patients with coronary heart disease, implicating their association with onset and progression of the disease. The biomarkers were found to be correlated with coronary artery calcium score. Detection of changes of related biomarkers in serum may have certain value in diagnosis of disease formation, as well as assessment of disease severity.

Hemodynamics mediated epigenetic regulators in the pathogenesis of vascular diseases

Endothelium of blood vessels is continuously exposed to various hemodynamic forces. Flow-mediated epigenetic plasticity regulates vascular endothelial function. Recent studies have highlighted the significant role of mechanosensing-related epigenetics in localized endothelial dysfunction and the regional susceptibility for lesions in vascular diseases. In this article, we review the epigenetic mechanisms such as DNA de/methylation, histone modifications, as well as non-coding RNAs in promoting endothelial dysfunction in major arterial and venous diseases, consequent to hemodynamic alterations. We also discuss the current challenges and future prospects for the use of mechanoepigenetic mediators as biomarkers of early stages of vascular diseases and dysregulated mechanosensing-related epigenetic regulators as therapeutic targets in various vascular diseases.

MicroRNA-126 Modulates Palmitate-Induced Migration in HUVECs by Downregulating Myosin Light Chain Kinase via the ERK/MAPK Pathway

MicroRNA-126 (miR-126) is an endothelial-specific microRNA that has shown beneficial effects on endothelial dysfunction. However, the underlying molecular mechanism is unclear. The present study evaluated the effects of miR-126 on the cell migration and underlying mechanism in HUVECs treated with palmitate. The present results demonstrated that overexpression of miR-126 was found to decrease cell migration in palmitate-treated HUVECs, with decreased MLCK expression and subsequent decreased phosphorylated MLC level. miR-126 also decreased the phosphorylation of MYPT1 in palmitate-treated HUVECs. In addition, it was demonstrated that miR-126 decreases expression of the NADPH oxidase subunits, p67 and Rac family small GTPase 1 with a subsequent decrease in cell apoptosis. Moreover, the phosphorylation of ERK was reduced by miR-126 in palmitate-induced HUVECs. Taken together, the present study showed that the effect of miR-126 on cell migration and cell apoptosis is mediated through downregulation of MLCK via the ERK/MAPK pathway.

Long-Term Exercise Alters the Profiles of Circulating Micro-RNAs in the Plasma of Young Women

Objective: The objective of this paper was to study the effects of long-term exercise on circulating microRNAs (miRNAs) in human plasma.

Methods: Whole blood was collected from 10 female elite athletes with at least 5 years of training experience in a Synchronized Swimming Group (S group) and 15 female college students without regular exercise training (C group). Plasma miRNAs were then isolated, sequenced, and semi-quantified by the second-generation sequencing technology, and the results were analyzed by bioinformatics methods.

Results: We found 380 differentially expressed miRNAs in the S group compared with the C group, among which 238 miRNAs were upregulated and 142 were downregulated. The top five abundant miRNAs in the 380 miRNAs of the S group are hsa-miR-451a, hsa-miR-486, hsa-miR-21-5p, hsa-miR-423-5p, and hsa-let-7b-5p. Muscle-specific/enriched miRNAs were not significantly different, except for miR-206 and miR-486. According to the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis, a large proportion of the differentially expressed miRNAs are targeted in cancer-related pathways, including proteoglycans in cancer and miRNAs in cancer and basal cell carcinoma. As the levels of circulating miRNAs (ci-miRNAs) are commonly known to be significantly deregulated in cancer patients, we further compared the levels of some well-studied miRNAs in different types of cancer patients with those in the S group and found that long-term exercise regulates the level of ci-miRNAs in an opposite direction to those in cancer patients.

Conclusion: Long-term exercise significantly alters the profiles of plasma miRNAs in healthy young women. It may reduce the risk of certain types of cancers by regulating plasma miRNA levels.

MicroRNA-126: Dual Role in Angiogenesis Dependent Diseases

BACKGROUND

MicroRNA-126, a microRNA implicated in blood vessel integrity and angiogenesis is significantly up/down regulated in different physiological and pathological conditions related to angiogenesis such as cardiovascular formation and angiogenesis dependent diseases. MicroRNA-126 plays a critical role in angiogenesis via regulating the proliferation, differentiation, migration, and apoptosis of angiogenesis related cells such as endothelial cells.

OBJECTIVE

The aim of this review is to investigate the molecular mechanisms and the effects of microRNA-126 on the process of angiogenesis in pathophysiological conditions.

METHODS

To conduct this review, related articles published between 2001 and 2019 were collected from the PubMed, Web of Science, Google Scholar, Scopus and Scientific Information Database using search terms such as microRNA-126, angiogenesis, cardiovascular disorders, hypoxia, VEFG-A, endothelial cells, VEGF pathway, and gene silencing. Then, the qualified articles were reviewed.

RESULTS

MicroRNA-126 regulates the response of endothelial cells to VEGF, through directly repressing multiple targets, including Sprouty-related EVH1 domain-containing protein 1 (SPRED1) and phosphoinositol-3 kinase regulatory subunit 2 (PIK3R2/p85-b). MicroRNA-126 -3p and microRNA-126 -5p have cell-type and strandspecific functions and also various targets in angiogenesis that lead to the regulation of angiogenesis via different pathways and consequently diverse responses.

CONCLUSION

MicroRNA-126 can bind to multiple targets and potentially be both positive and negative regulators of gene expression. Thus, microRNA-126 could cause the opposite biological effects depending on the context. As a result, understanding the different cellular pathways through which microRNA-126 regulates angiogenesis in various situations is a critical aspect in the development of novel and effective treatments for diseases with insufficient angiogenesis.

From animal models to patients: the role of placental microRNAs, miR-210, miR-126, and miR-148a/152 in preeclampsia

Placental microRNAs (miRNAs) regulate the placental transcriptome and play a pathological role in preeclampsia (PE), a hypertensive disorder of pregnancy. Three PE rodent model studies explored the role of placental miRNAs, miR-210, miR-126, and miR-148/152 respectively, by examining expression of the miRNAs, their inducers, and potential gene targets. This review evaluates the role of miR-210, miR-126, and miR-148/152 in PE by comparing findings from the three rodent model studies with in vitro studies, other animal models, and preeclamptic patients to provide comprehensive insight into genetic components and pathological processes in the placenta contributing to PE. The majority of studies demonstrate miR-210 is upregulated in PE in part driven by HIF-1α and NF-κBp50, stimulated by hypoxia and/or immune-mediated processes. Elevated miR-210 may contribute to PE via inhibiting anti-inflammatory Th2-cytokines. Studies report an up- and downregulation of miR-126, arguably reflecting differences in expression between cell types and its multifunctional capacity. MiR-126 may play a pro-angiogenic role by mediating the PI3K-Akt pathway. Most studies report miR-148/152 family members are upregulated in PE. Evidence suggests they may inhibit DNA methylation of genes involved in metabolic and inflammatory pathways. Given the genetic heterogeneity of PE, it is unlikely that a single placental miRNA is a suitable therapeutic target for all patients. Investigating miRNAs in PE subtypes in patients and animal models may represent a more appropriate approach going forward. Developing methods for targeting placental miRNAs and specific placental cell types remains crucial for research seeking to target placental miRNAs as a novel treatment for PE.

Noncoding RNAs as Biomarkers for Acute Coronary Syndrome

Acute coronary syndrome (ACS), consisting of acute myocardial infarction and unstable angina, is the most dangerous and fatal form of coronary heart disease. Acute coronary syndrome has sudden onset and rapid development, which may lead to malignant life-threatening conditions at any time. Therefore, early detection and diagnosis are critical for patients with ACS. Recent studies have found that noncoding RNA is of great significance in the diagnosis and treatment of cardiovascular diseases. In this review, we summarized recent data on circulating noncoding RNAs (including microRNA, long noncoding RNA, and circular RNA) as diagnostic and prognostic markers in ACS including acute myocardial infarction and unstable angina. Specifically, microRNAs (miRNAs) as diagnostic markers are divided into three types: miRNAs of increased expression in ACS, miRNAs of decreased expression in ACS, and miRNAs of contradictory expression in ACS. Moreover, we described these miRNAs of increased expression in ACS based on miRNAs family. This review may result in a great guidance of noncoding RNAs as biomarkers for ACS in clinical practice.

A prospective case-control study on miRNA circulating levels in subjects born small for gestational age (SGA) evaluated from childhood into young adulthood

OBJECTIVE

microRNAs (miRNAs) associated with metabolic risk have never been extensively investigated in SGA subjects. The aim of the current study was to evaluate miRNAs in SGA and AGA subjects and their relationships with the metabolic status and growth.

DESIGN AND METHODS

A prospective longitudinal case-control study was performed in 23 SGA with postnatal catch-up growth and 27 AGA subjects evaluated at the age of 9 and 21 years. Circulating levels of miR-122-5p, miR-16-5p, miR-126-3p, and miR-486-5p were assessed by qPCR.

RESULTS

SGA subjects were shorter both at 9 and at 21 years. No significant differences in insulin like growth factors and metabolic profile were found with the exception of basal glycemia at 9 years. miRNA levels did not differ between SGA and AGA subjects, at 9 and 21 years. miR-16-5p and miR-126-3p levels were higher at 9 than at 21 years. In SGA subjects, miR-122-5p at 9 years was inversely related to adiponectin levels at 21 years and miR-486-5p at 9 years was inversely related to whole-body insulin sensitivity at 9 years and directly related to Hb1Ac at 21 years. Regression analyses showed no predictive value of miRNAs for growth parameters in neither SGA nor AGA subjects.

CONCLUSIONS

SGA with postnatal catch-up growth did not show any difference in metabolic risk markers or miRNA circulating levels compared to AGA controls in childhood and young adulthood. miR-122-5p during childhood could identify SGA subjects at higher risk of developing insulin resistance and, eventually, type 2 diabetes in adulthood but further studies are needed to confirm it.

Oxidative Stress-Responsive MicroRNAs in Heart Injury

Reactive oxygen species (ROS) are important molecules in the living organisms as a part of many signaling pathways. However, if overproduced, they also play a significant role in the development of cardiovascular diseases, such as arrhythmia, cardiomyopathy, ischemia/reperfusion injury (e.g., myocardial infarction and heart transplantation), and heart failure. As a result of oxidative stress action, apoptosis, hypertrophy, and fibrosis may occur. MicroRNAs (miRNAs) represent important endogenous nucleotides that regulate many biological processes, including those involved in heart damage caused by oxidative stress. Oxidative stress can alter the expression level of many miRNAs. These changes in miRNA expression occur mainly via modulation of nuclear factor erythroid 2-related factor 2 (Nrf2), sirtuins, calcineurin/nuclear factor of activated T cell (NFAT), or nuclear factor kappa B (NF-κB) pathways. Up until now, several circulating miRNAs have been reported to be potential biomarkers of ROS-related cardiac diseases, including myocardial infarction, hypertrophy, ischemia/reperfusion, and heart failure, such as miRNA-499, miRNA-199, miRNA-21, miRNA-144, miRNA-208a, miRNA-34a, etc. On the other hand, a lot of studies are aimed at using miRNAs for therapeutic purposes. This review points to the need for studying the role of redox-sensitive miRNAs, to identify more effective biomarkers and develop better therapeutic targets for oxidative-stress-related heart diseases.

Non-coding RNAs and Coronary Artery Disease

Coronary artery disease (CAD) is the leading death cause worldwide. Non-coding RNA (ncRNA) are key regulators of genetic expression and thus can affect directly or indirectly the development and progression of different diseases. ncRNA can be classified in several types depending on the length or structure, as long non-coding RNA (lncRNA), microRNA (miRNA) and circularRNA (circRNA), among others. These types of RNA are present within cells or in circulation, and for this reason they have been used as biomarkers of different diseases, therefore revolutionizing precision medicine. Recent research studied the capability of circulating ncRNA to inform about CAD presence and predict the outcome of the disease. In this chapter we present a list of the miRNA, lncRNA and circRNA which are potential biomarkers of CAD.

MicroRNAs as Therapeutic Targets and Clinical Biomarkers in Atherosclerosis

Atherosclerotic cardiovascular disease remains the leading cause of morbidity and mortality worldwide. Atherosclerosis develops over several decades and is mediated by a complex interplay of cellular mechanisms that drive a chronic inflammatory milieu and cell-to-cell interactions between endothelial cells, smooth muscle cells and macrophages that promote plaque development and progression. While there has been significant therapeutic advancement, there remains a gap where novel therapeutic approaches can complement current therapies to provide a holistic approach for treating atherosclerosis to orchestrate the regulation of complex signalling networks across multiple cell types and different stages of disease progression. MicroRNAs (miRNAs) are emerging as important post-transcriptional regulators of a suite of molecular signalling pathways and pathophysiological cellular effects. Furthermore, circulating miRNAs have emerged as a new class of disease biomarkers to better inform clinical diagnosis and provide new avenues for personalised therapies. This review focusses on recent insights into the potential role of miRNAs both as therapeutic targets in the regulation of the most influential processes that govern atherosclerosis and as clinical biomarkers that may be reflective of disease severity, highlighting the potential theranostic (therapeutic and diagnostic) properties of miRNAs in the management of cardiovascular disease.

The Influence of Diet on MicroRNAs that Impact Cardiovascular Disease

Food quality and nutritional habits strongly influence human health status. Extensive research has been conducted to confirm that foods rich in biologically active nutrients have a positive impact on the onset and development of different pathological processes, including cardiovascular diseases. However, the underlying mechanisms by which dietary compounds regulate cardiovascular function have not yet been fully clarified. A growing number of studies confirm that bioactive food components modulate various signaling pathways which are involved in heart physiology and pathology. Recent evidence indicates that microRNAs (miRNAs), small single-stranded RNA chains with a powerful ability to influence protein expression in the whole organism, have a significant role in the regulation of cardiovascular-related pathways. This review summarizes recent studies dealing with the impact of some biologically active nutrients like polyunsaturated fatty acids (PUFAs), vitamins E and D, dietary fiber, or selenium on the expression of many miRNAs, which are connected with cardiovascular diseases. Current research indicates that the expression levels of many cardiovascular-related miRNAs like miRNA-21, -30 family, -34, -155, or -199 can be altered by foods and dietary supplements in various animal and human disease models. Understanding the dietary modulation of miRNAs represents, therefore, an important field for further research. The acquired knowledge may be used in personalized nutritional prevention of cardiovascular disease or the treatment of cardiovascular disorders.

The inhibition of miR-126 in cell migration and invasion of cervical cancer through regulating ZEB1

Background

Cervical cancer is a malignancy that’s common in female with high incidence and mortality worldwide. MicroRNAs (miRNAs) act a pivotal part in human cancer development. Our aim was to investigate the effect of miR-126 on cervical cancer and its underlying molecular mechanism.

Results

Firstly, RT-qPCR assay revealed that the expression of miR-126 was significantly downregulated in cervical cancer tissues and cell lines, compared with that in normal adjacent tissues and normal cervical epithelial cell line (Ect1/E6E7), respectively. Then, ZEB1 was verified as a target of miR-126 by using luciferase reporter assay. Inversely, the expression of ZEB1 was markedly upregulated in tumor tissues, and its mRNA level was negatively regulated by miR-126 expression in SiHa and Hela cells. Moreover, the capability of cell proliferation, migration and invasion was analyzed by CCK-8, wound healing assay and transwell assay, respectively. The results demonstrated that overexpression of miR-126 inhibited SiHa and Hela cell proliferation, migration and invasion, while ZEB1 abolished the inhibition induced by miR-126. Additionally, miR-126 suppressed MMP2 and MMP9 in mRNA and protein levels, as well as inhibited the protein expression of p-JAK2 and p-STAT3 in both SiHa and Hela cells, while ZEB1 rescued miR-126-induced suppression.

Conclusion

miR-126 functions as a tumor suppressor in cervical cancer cells in vitro, which inhibits the proliferation, migration and invasion by suppressing MMP2, MMP9 expression and inactivating JAK2/STAT3 signaling pathway through targeting ZEB1, suggesting that miR-126 might be a novel potential target for the diagnosis and treatment of patients with cervical cancer.

Upregulation of MiR-126 Delays the Senescence of Human Glomerular Mesangial Cells Induced by High Glucose via Telomere-p53-p21-Rb Signaling Pathway

Diabetic kidney disease (DKD) is a microvascular complication of type 2 diabetes. The study of DKD mechanisms is the most important target for the prevention of DKD. Renal senescence is one of the important pathogeneses for DKD, but the mechanism of renal and cellular senescence is unclear. Decreased expression of circulating miR-126 is associated with the development of DKD and may be a promising blood-based biomarker for DKD. This study is to probe the effect and mechanism of miR-126 on the aging of human glomerular mesangial cells (HGMCs) induced by high glucose. HGMCs were cultured with Roswell Park Memorial Institute (RPMI-1640) in vitro. The effect of high glucose on morphology of HGMCs was observed 72 h after intervention. The cell cycle was examined by flow cytometry. The telomere length was measured by Southern blotting. The expression levels of p53, p21 and Rb proteins in p53-p21-Rb signaling pathway and p-stat1, p-stat3 in JAK/STAT signaling pathway were detected by Western blotting respectively. The expression of miR-126 was examined by qRT-PCR. MiR-126 mimics was transfected into HGMCs. The effects of miR-126 mimics transfection on cell morphology, cell cycle, telomere length, p53, p21, Rb, p-stat1 and p-stat3 were observed. The results showed that high glucose not only arrested the cell cycle in G1 phase but also shortened the telomere length. High glucose led to high expression of p53, p21, Rb, p-stat1 and p-stat3 and premature senescence of HGMCs by activating the telomere-p53-p21-Rb and JAK/STAT signaling pathways. Moreover, the miR-126 was decreased in HGMCs induced by high glucose. It was suggested that the transfection of miR-126 mimics could inhibit the telomere-p53-p21-Rb and JAK/STAT signaling pathway activity in vitro and delay the senescence of HGMCs. The results may serve as a new strategy for the treatment of DKD.

At the heart of programming: the role of micro-RNAs

Epidemiological and experimental observations tend to prove that environment, lifestyle or nutritional challenges influence heart functions together with genetic factors. Furthermore, when occurring during sensitive windows of heart development, these environmental challenges can induce an 'altered programming' of heart development and shape the future heart disease risk. In the etiology of heart diseases driven by environmental challenges, epigenetics has been highlighted as an underlying mechanism, constituting a bridge between environment and heart health. In particular, micro-RNAs which are involved in each step of heart development and functions seem to play a crucial role in the unfavorable programming of heart diseases. This review describes the latest advances in micro-RNA research in heart diseases driven by early exposure to challenges and discusses the use of micro-RNAs as potential targets in the reversal of the pathophysiology.